Pushed dethatching unit

Abstract

A dethatching unit is mounted for attachment to the front end of a self-propelled lawn mower, for example, so that the dethatching unit is pushed by the lawn mower and thatches the ground prior to mowing thereof. The dethatching unit includes a frame having a caster wheel at its forward end and arms at its rear end for attaching to the mower. The wheel and the arms cooperate so that tines, which are mounted in two rows on the frame, do not carry any of the weight of the unit so that the bottom tip of each of the tines is slightly spaced from the ground in its rest position. Each of the tines in each of the rows is offset from each of the tines in the other row. Forward motion of the dethatching unit causes the bottom tip of each of the tines to deflect rearwardly and downwardly as it comes in contact with grass. In their deflected positions, the bottom tips of the tines contact the thatch layer to tear it loose from the soil and ultimately flip the thatched material to fall on the ground. This leaves the thatched material loose for the vacuum effect of a mower to pick up and collect in a bag. The flipping or release action of the tines occurs periodically as the caster wheel runs over grass clumps or uneven ground. If desired, this release action can be controlled by use of a non-circular wheel. The questions raised in reexamination request No. 90/000,405, filed 06/20/83, have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U.S.C. 307 as provided in 37 CFR 1.570(e).

I claim: 
     
       1. A pushed dethatching unit .Iadd.for removing thatch material from a layer of thatch and .Iaddend.including: frame means;   wheel means supported adjacent the front end of said frame means to support said frame means;   said frame means having at least one row of tines mounted thereon, each of said tines in each of said rows being non-rotary;   each of said tines in each of said rows of said tines being offset in the direction of motion of said dethatching unit from each of said tines in each of said other rows of said tines when there is more than one of said rows of said tines;   each of said tines having a lower portion .Iadd.terminating in a tip .Iaddend.for engaging the material to be thatched;   and support means supported adjacent the rear end of said frame means to attach said frame means to pushing means to enable pushing of said dethatching unit by the pushing means, said support means and said wheel means cooperating to suspend the .[.bottom.]. tip of said lower portion of each of said tines above the ground so that no weight is applied to any of said tines when said dethatching unit is at rest, and each of said tines having the .[.bottom.]. tip of said lower portion beneath the point of attachment of said support means to the pushing means at all times.[...]..Iadd.; .Iaddend.   .Iadd.said tines extending downwardly and forwardly from said frame means with each said tip disposed above the ground such that forward motion of said pushed dethatching unit causes said tine tips to deflect downwardly and rearwardly, upon contact with grass, and into contact with thatch material to tear contacted material loose from a layer of thatch. .Iaddend.   
     
     
       2. The pushed dethatching unit according to claim 1 in which said support means includes cooperating means to prevent said dethatching unit from moving into engagement with the pushing means when said dethatching unit is lifted for turning the pushing means. 
     
     
       3. The pushed dethatching unit according to claim 2 in which: each of said tines has .Iadd.an upper portion and .Iaddend.a coiled portion connected to said upper portion;   connecting means to connect said coiled portion of each adjacent pair of said tines to each other;   means to attach said connecting means to said frame means;   and means supported by said frame means and extending through said coiled portion of each of said tines in each of said rows to catch said tine if it breaks.   
     
     
       4. The pushed dethatching unit according to claim 3 including: means to vertically adjust said wheel means relative to said frame means;   and means to adjust the position of said support means relative to said frame means to adjust the plane of the .[.bottom.]. tip of said lower portion of each of said tines.   
     
     
       5. The pushed dethatching unit according to claim 1 in which said support means includes: extending means extending rearwardly from each side of said frame means;   and means supported on said extending means for releasably connecting said dethatching unit to the pushing means.   
     
     
       6. The pushed dethatching unit according to claim 5 including means to adjust the position of said extending means relative to said frame means to adjust the plane of the .[.bottom.]. tip of said lower portion of each of said tines. 
     
     
       7. The pushed dethatching unit according to claim 6 including means to vertically adjust said wheel means relative to said frame means. 
     
     
       8. The pushed dethatching unit according to claim 5 in which: each of said tines has .Iadd.an upper portion and .Iaddend.a coiled portion connected to said upper portion;   connecting means to connect said coiled portion of each adjacent pair of said tines to each other;   means to attach said connecting means to said frame means;   and means supported by said frame means and extending through said coiled portion of each of said tines in each of said rows to catch said tine if it breaks.   
     
     
       9. The pushed dethatching unit according to claim 1 in which said frame means includes: first means having each of said tines mounted thereon;   and second means secured to said first means and having said wheel means mounted thereon.   
     
     
       10. The pushed dethatching unit according to claim 1 in which said wheel means includes a single caster wheel supported by said frame means. 
     
     
       11. The pushed dethatching unit according to claim 1 in which each of said tines has an upper portion and said lower portion is inclined forwardly of said upper portion at least when said tine is at rest. 
     
     
       12. The pushed dethatching unit according to claim 1 in which: said frame means includes: upper frame means;   lower frame means;   means to connect said lower frame means to said upper frame means in suspended relation thereto;   said upper frame means supporting said wheel means;   said lower frame means having said tines mounted thereon;   and said support means being supported by said lower frame means.     
     
     
       13. The pushed dethatching unit according to claim 12 including: means to vertically adjust said wheel means relative to said upper frame means;   and means to adjust the position of said support means relative to said lower frame means to adjust the plane of the .[.bottom.]. tip of said lower portion of each of said tines.   
     
     
       14. The pushed dethatching unit according to claim 13 in which said wheel means includes a single caster wheel supported by said upper frame means. 
     
     
       15. The pushed dethatching unit according to claim 12 in which said support means includes: extending means extending rearwardly from each side of said lower frame means;   and means supported on said extending means for releasably connecting said dethatching unit to the pushing means.   
     
     
       16. The pushed dethatching unit according to claim 15 in which: said extending means includes a pair of arms;   each of said arms includes said supported means of said support means;   means to pivotally connect each of said arms to said lower frame means for independent pivoting;   and means to lock each of said arms separately in any position to which said arm is pivoted to adjust the plane of the .[.bottom.]. tip of said lower portion of each of said tines.   
     
     
       17. The pushed dethatching unit according to claim 16 in which: each of said tines has .Iadd.an upper portion and .Iaddend.a coiled portion connected to said upper portion;   connecting means to connect said coiled portion of each adjacent pair of said tines to each other;   means to attach said connecting means to said lower frame means;   catching means supported by said lower frame means and extending through said coiled portion of each of said tines in each of said rows to catch said tine if it breaks;   and said catching means for one of said rows of said tines includes said pivoting means for said arms.   
     
     
       18. The pushed dethatching unit according to claim 12 in which each of said tines has an upper portion and said lower portion is inclined forwardly of said upper portion at least when said tine is at rest. .Iadd. 
     
     
       19.  The pushed dethatching unit according to claim 1 in which: each of said tines has a coiled portion adjacent said frame means;   said catching means supported by said frame and extending through said coiled portion of each of said tines to catch said tine if it breaks. .Iaddend. .Iadd.20. The pushed dethatching unit according to claim 5 in which:   each of said tines has a coiled portion adjacent said frame means;   and catching means supported by said frame means and extending through said coiled portion of each of said tines to catch said tine if it breaks. .Iaddend. .Iadd.21. The pushed dethatching unit according to claim 1 in which each of said tines has its tip rearwardly of the engagement of said wheel means with the ground when said dethatching unit is at rest. .Iaddend. .Iadd.22. The pushed dethatching unit according to claim 5 in which each of said tines has its tip rearwardly of the engagement of said wheel means with the ground when said dethatching unit is at rest. .Iaddend. .Iadd.23. The pushed dethatching unit according to claim 1 in which:   each of a plurality of said tines has its tip in a single row;   and each of said tines having its tip in the single row is movable downwardly and rearwardly from its rest position for engaging the material   
     
     
        to be thatched. .Iaddend. .Iadd.24.  The pushed dethatching unit according to claim 23 in which each of said tines movable downwardly and rearwardly has an upper portion and said lower portion is inclined forwardly of said upper portion at least when said tine is at rest. .Iaddend. .Iadd.25. The pushed dethatching unit according to claim 5 in which: each of a plurality of said tines has its tip in a single row;   and each of said tines having its tip in the single row is movable downwardly and rearwardly from its rest position for engaging the material to be thatched. .Iaddend. .Iadd.26. The pushed dethatching unit according to claim 25 in which each of said tines movable downwardly and rearwardly has an upper portion and said lower portion is inclined forwardly of said upper portion at least when said tine is at rest. .Iaddend. .Iadd.27. The pushed dethatching unit according to claim 12 in which:   each of said tines has a coiled portion adjacent said lower frame means;   and catching means supported by said lower frame means and extending through said coiled portion of each of said tines to catch said tine if it   
     
     
        breaks. .Iaddend. .Iadd.28.  The pushed dethatching unit according to claim 13 in which: each of said tines has a coiled portion adjacent said lower frame means;   and catching means supported by said lower frame means and extending through said coiled portion of each of said tines to catch said tine if it breaks. .Iaddend. .Iadd.29. The pushed dethatching unit according to claim 16 in which:   each of said tines has a coiled portion adjacent said lower frame means;   and catching means supported by said lower frame means and extending through said coiled portion of each of said tines to catch said tine if it breaks. .Iaddend. .Iadd.30. The pushed dethatching unit according to claim 29 including:   a plurality of rows of said tines;   and said catching means for one of said rows of said tines includes said   
     
     
        pivoting means for said arms. .Iaddend. .Iadd.31.  The pushed dethatching unit according to claim 1 in which said support means supported on said frame means is separate from said frame means. .Iaddend. .Iadd.32. The pushed dethatching unit according to claim 5 in which: each of said extending means is separate from said lower frame means;   and said supported means supported on said extending means is supported solely on said extending means. .Iaddend. .Iadd.33. The pushed dethatching unit according to claim 1 in which said support means includes:   extending means extending rearwardly from each side of said frame means;   and latch means supported solely on said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend. .Iadd.34. The pushed dethatching unit according to claim 12 in which said support means includes:   extending means extending rearwardly from each side of said lower frame means;   and latch means supported solely on said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend.   
     
     
        .Iadd.     A pushed dethatching unit for removing thatch material from a layer of thatch and including: frame means;   wheel means supported adjacent the front end of said frame means to support said frame means;   said frame means having at least one row of tines mounted thereon, each of said tines being mounted for movement independently of each of the other of said tines;   each of said tines having a lower portion terminating in a tip for engaging the material to be thatched;   and support means supported adjacent the rear end of said frame means to attach said frame means to pushing means to enable pushing of said dethatching unit by the pushing means, said lower portion of each of said tines having its tip above the ground so that no weight is applied to any of said tines when said dethatching unit is at rest, and each of said tines having the bottom tip of said lower portion beneath the point of attachment of said support means to the pushing means at all times; said tines extending downwardly and forwardly from said frame means with each said tip portion disposed above the ground such that forward motion of said pushed dethatching unit causes said tine tip portions to deflect downwardly and rearwardly, upon contact with grass, and into contact with thatch material to tear contacted material loose from a layer of thatch.   
     
     
        .Iaddend. .Iadd.36.  The pushed dethatching unit according to claim 35 including: said frame means having a plurality of rows of said tines mounted thereon;   and each of said tines in each of said rows of said tines being offset in the direction of motion of said dethatching unit from each of said tines in each of said other rows of said tines. .Iaddend. .Iadd.37. The pushed dethatching unit according to claim 35 including:   said frame means having said tines mounted thereon to dispose said tips of said tines in a plurality of rows;   and each of said tines having said tips in each of said rows offset in the direction of motion of said dethatching unit from each of said tines having said tips in each of said other rows of said tips. .Iaddend. .Iadd.38. The pushed dethatching unit according to claim 37 in which each of said tines having its tip in at least one of the plurality of rows is movable downwardly and rearwardly from its rest position for engaging the   
     
     
        material to be thatched. .Iaddend. .Iadd.39.  The pushed dethatching unit according to claim 35 in which each of said tines has its tip rearwardly of the engagement of said wheel means with the ground when said dethatching unit is at rest. .Iaddend. .Iadd.40. The pushed dethatching unit according to claim 35 in which: each of said tines has a coiled portion adjacent said frame means;   and catching means supported by said frame means and extending through said coiled portion of each of said tines to catch said tine if it breaks. .Iaddend. .Iadd.41. The pushed dethatching unit according to claim 35 in which:   each of a plurality of said tines has its tip in a single row;   and each of said tines having its tip in a single row is movable downwardly and rearwardly from its rest position for engaging the material to be   
     
     
        thatched. .Iaddend. .Iadd.42.  The pushed dethatching unit according to claim 35 in which said frame means includes: upper frame means supporting said wheel means;   lower frame means having said tines mounted thereon;   said lower frame means and said upper frame means being connected to each other;   and said support means being supported by said lower frame means. .Iaddend. .Iadd.43. The pushed dethatching unit according to claim 42 including:   said support means and said wheel means cooperating to suspend the bottom tip of said lower portion of each of said tines above the ground so that no weight is applied to any of said tines when said dethatching unit is at rest;   means to vertically adjust said wheel means relative to said upper frame means;   and means to adjust the position of said support means relative to said lower frame means to adjust the plane of the bottom tip of said lower portion of each of said tines. .Iaddend. .Iadd.44. The pushed dethatching unit according to claim 43 in which said wheel means includes a single   
     
     
        caster wheel supported by said upper frame means. .Iaddend. .Iadd.45.  The pushed dethatching unit according to claim 42 in which said support means includes: extending means extending rearwardly from each side of said lower frame means;   and means supported on said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend. .Iadd.46. The pushed dethatching unit according to claim 45 in which:   said extending means includes a pair of arms;   each of said arms includes said supported means of said support means;   means to pivotally connect each of said arms to said lower frame means for independent pivoting;   and means to lock each of said arms separately in any position to which said arm is pivoted to adjust the plane of the bottom tip of said lower   
     
     
        portion of each of said tines. .Iaddend. .Iadd.47.  The pushed dethatching unit according to claim 46 in which: each of said tines has a coiled portion adjacent said lower frame means;   and catching means supported by said lower frame means and extending through said coiled portion of each of said tines to catch said tine if it breaks. .Iaddend. .Iadd.48. The pushed dethatching unit according to claim 35 in which said support means includes:   extending means extending rearwardly from each side of said frame means;   and means supported on said extending means for releasably connecting said   
     
     
        dethatching unit to the pushing means. .Iaddend. .Iadd.49.  The pushed dethatching unit according to claim 48 including means to adjust the position of said extending means relative to said frame means to adjust the plane of the bottom tip of said lower portion of each of said tines. .Iaddend. .Iadd.50. The pushed dethatching unit according to claim 35 in which said support means includes cooperating means to prevent said dethatching unit from moving into engagement with the pushing means when said dethatching unit is lifted for turning the pushing means. .Iaddend. 
     
     
        .Iadd.51.  The pushed dethatcing unit according to claim 35 in which said support means supported on said frame means is separate from said frame means. .Iaddend. .Iadd.52. The pushed dethatching unit according to claim 48 in which: each of said extending means is separate from said lower frame means;   and said supported means supported on said extending means is supported   
     
     
        solely on said extending means. .Iaddend. .Iadd.53.  The pushed dethatching unit according to claim 35 in which said support means includes: extending means extending rearwardly from each side of said frame means;   and latch means supported solely on said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend. .Iadd.54. The pushed dethatching unit according to claim 42 in which said support means includes:   extending means extending rearwardly from each side of said lower frame means;   and latch means supported solely on said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend.   
     
     
        .Iadd.     A pushed dethatching unit for removing thatch material from a layer of thatch and including: frame means;   wheel means for supporting said frame means;   said frame means having a plurality of tines mounted thereon for movement independently of each other;   each of said independently movable tines having a lower portion for engaging the material to be thatched;   each of said independently movable tines being movable downwardly and rearwardly from its rest position for engaging the material to be thatched;   and attaching means for attaching said frame means to pushing means to enable pushing of said dethatching unit by the pushing means, said lower portion of each of said independently movable tines terminating in a tip disposed above the ground so that no weight is applied to any of said independently movable tines when said dethatching unit is at rest whereupon forward motion of said pushed dethatching unit causes each of said tines to deflect downwardly and rearwardly as it comes into contact with grass, so that each of said tips contacts thatch material to tear it   
     
     
        loose and flip it away from a layer of thatch. .Iaddend. .Iadd.56.  The pushed dethatching unit according to claim 55 in which said attaching means includes: extending means extending rearwardly from said frame means;   and releasably connecting means supported by said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend. .Iadd.57. The pushed dethatching unit according to claim 56 in which:   said extending means includes a pair of arms;   each of said arms solely supporting one of said releasably connecting means;   means to pivotally connect each of said arms to said frame means for independent pivoting;   and means to lock each of said arms separately in any position to which said arm is pivoted to adjust the plane of the bottom tip of said lower portion of each of said independently movable tines. .Iaddend. .Iadd.58. The pushed dethatching unit according to claim 55 in which:   said frame means includes upper frame means and lower frame means separate from each other and connected to each other;   one of said lower frame means and said upper frame means is connected to said wheel means;   and the other of said lower frame means and said upper frame means supports   
     
     
        said attaching means. .Iaddend. .Iadd.59.  The pushed dethatching unit according to claim 55 in which said support means includes: extending means extending rearwardly from each side of said frame means;   and latch means supported solely on said extending means for releasably connecting said dethatching unit to the pushing means. .Iaddend.   
     
     
        .Iadd.     A pushed dethatching apparatus for moving through grass and removing thatch material from a layer of thatch on the ground in which grass grows and including: frame means;   wheel means attached to said frame means to support said frame means;   a plurality of independently movable tines mounted on said frame means, each of said tines having a lower portion for engaging thatch material to be thatched;   means for supporting said frame means and for attaching said frame means to a pushing means to enable pushing of said dethatching apparatus through the grass and over the ground;   said lower portion of each of said tines having a tip supported above the ground so that no weight is applied to said tines when said dethatching apparatus is at rest;   and each of said tines extending downwardly from said frame means and being movable upon engagement with grass when said apparatus is pushed therethrough, the engagement of each of said tines with the grass deflecting said lower portion and tip of said tine to engage thatch material to be thatched, each of said tines flipping the thatched material up from a layer of thatch on the ground during further forward movement of said apparatus. .Iaddend.